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Journal Entry #1

Hanauma Bay is a Nature Preserve that is well-known for it’s great beautiful marine life which also attracts many tourists. I believe that this will be a great place to study because the life there is left more undisturbed than other places. People work hard to preserve the environment and I think that we will see a lot of life there. I think that the abundance of life will make our research more enjoyable and fuller.


There are many species that live in Hanauma Bay. Past the wall (which we are not going to be researching for safety reasons) there are many predators which include: sharks, barracuda, eels, larger fish. There are also octopuses, shrimps, crabs, and snails. On the inside portion of the wall you will see many smaller colorful reef fish which feed off of the coral heads and do not seem to be as afraid of people as most fish are. This is probably because of all the tourists visiting there everyday. They wouldn’t even mind me swimming within a few feet and they would let me get very close to take good underwater pictures.


One fish that I saw while swimming *pictures to come* was a rock fish that was very well-camoflauged. I saw this as indirect proof of a predator-prey relationship because of the fish’s need to hide itself. The fish may be prey trying to hide itself from predators, or it could be the predator waiting to launch itself at unsuspecting victims. I thought that the fish looked more like prey because of its size compared to the other fish nearby. I don’t think that it would be able to eat them! It could though be sneaking up on shrimps or baby fish, but that seems less likely.


Journal Entry #2

In our second trip to Hanauma Bay, we did a fish count. Our method was to swim out to the rock wall (approximately 100 yards) and count the number of times we would see a certain number of fish. We would repeat this step to make sure that our data was more accurate and to look for different types of fish. We took pictures of the fish we saw on under water cameras (to be developed) and we observed their behaviors to find any certain ways they eat, swim, school, place, etc.
As a group we saw (multiple numbers = multiple swims):
Convict Tangs: 60, 26; Average: 43
Orange Spine Unicorn Fish: 7
Racoon Butterfly: 6
Humuhumunukunukuapuaa(state fish): 7
Eel: 1
Needle/Cornet Fish: 1, 1; Average: 1
Parrot Fish: 1, 3; Average: 2
Moorish Idol: 3
Hawaiian White-Spotted Tobi(Puffer) : 5
Unicorn Fish: 3
*Pictures in process*
We could classify the types of fish because I had purchased a waterproof reef fish guide from the gift shop. We also learned, from the video, that Hamauma Bay was created from a lava flow about 40,000 years ago. This created a crater in near the shore that was flooded when water levels rose and in which, became Hanauma Bay. Hanauma Bay used to be a popular fishing site, but it was made a Nature Preserve because of over fishing in the area.

All of the fish we saw were living (or swimming) in relatively the same area. Many of them were eating off of the rocks (not sure what exactly that food was, maybe some sort of algae?) and if not, they were always near them. Where the Bay was sandy at the bottom there were almost no fish to be seen. I think that with all of these different types of fish living in the same area an eating similar food, there must be competition. I think that the Convict tangs have out competed some of the other fish because there are many more of them than other fish. Both Orange Spined Unicorn fish and Convict Tangs were eating off of the same rocks, but the convict tangs out numbered the unicorn fish. It could be that since the convict tangs are about half the size of the unicorn fish that they would be more abundant becasue they would not have to eat as much as the unicorn fish would to survive, but there were WAY more than twice as many tangs. There is definatelt competition in Hanauma Bay.


Journal Entry #3

The third time we went to Hanauma Bay we did a fish count, measure temperature of water, and the pH of the water. We also went earlier in the morning (8:00am-10:00am) because I heard that there are more fish feeding and therefore more fish/action to see. The weather was partly cloudy and it started to rain lightly at about 8:45am. The water was clear, but as it started to rain (clouds covered sun) it becasme harder to see and the water seemed more choppy. We conducted our fish count in a sightly different part of Haumana bay more towards the left and over shallower rocks. We saw many more fish in this area, but this may also be due to the time of the fish count.
One very interesting thing that I saw were two HUGE ulua chasing some smaller reef fish. They appeared out of nowhere and disappeared just as quickly. THe fish I was watching had obviously sensed them before I did becasue they darted away a short time before the ulua came swimming through. They were chasing many different types of reef fish, but especially unicorn fish. I tried to snap a picuture of them, but i wasn't fast enough. This is a good example of a predator-prey relationship between the ulua and small reef fish.

My Fish Count (swimming out to rocks and back):
Ulua: 2
Hawaiian White-Spotted Tobi (Puffer) Endemic: 5, 3
Black Spotted Sergeant: 6, 8 (seem to be territorial. seen chasing much larger fish away from a certain area)
Parrot Fish: 4 (feeding off rocks with their large powerful mouths)
Raccoon Butterfly: 1
Hawaiian Dascyllus: 4
Moorish Idol - 1
Yellow Goatfish - 7

The temperature of..
shorline water: 80.2F
15 feet out: 79.8F
Near rocks: 77.5F
The water seems to get colder as the water is deeper/farther out.

Air Temerature: 87F
Water pH(acidity): 8.1

Hypotheses:

If fish feed in the morning, then their food source is more abundant. What is it that makes fish seem more lively in the morning and more abundant in the morning than in the afternoon?

If Ulua are predators they are generalists because they eat all types of fish. What types of fish do they eat? Do they just go after any fish they see?

• Describe some of the environmental pressures that could be driving Natural Selection in your eco-zone

Some pressures that could be driving Natural selection in Hanauma Bay are: tourism, food supply, predation.
Hanauma Bay is one of the hot tourist sots in Hawaii. Everyday, many tourist from Japan, the mainland, etc. Tourism helps to benefit Hanauma Bay by bringing money, but may also hurt it. Tourists can disturb the habitat and may harm the bay. THere is possible litter and the possiblity of tourists hurting the coral and life on the reef when they step on it. Also, chemicals in sunscreen, de-fogging solution in snorkel masks and anything else that they ight bring in the water with them could potentially harm reef. This would lead to the lack of food. When there is not enough food, organisms compete for it and will hurt their chances of survival. The more fit organisms will eventualy populate the area and the weak will die out. This is an example of natural selection. Predation (such as the uluas) also affects the organisms (mostly fish) living in Hanauma Bay. The faster and stronger will be able to escape more easily and the slower and weaker will be eaten. These are some pressures that drive natural selection.


Journal Entry #4:


The fourth time I went to Hanauma Bay, it was very overcast and cold out. I went at 8:30 in the morning to count the fish at an earlier time of day. I did a fish count, took the temperature of the water, and the pH of the water. The water was very choppy and it was more difficult to see things. I didn't even try to take picture because I knew that would come out really blurry. I conducted the fish count in the same area as I did last time (center left over the shallow rocks where there seem to be more fish). There did not seem to be any huge effect on the area from the flooding and rain, which I had thought there might have been. I did not see anything much out of the ordinary although I did spot an eel sliding through the coral. I did the fish count about 8 or 9 times and found these (see data table)

Fish count:(multiple number = counted multiple times on different swims)

Eel:1 Hawaiian White-Spotted Tobi (Puffer): 7
Parrot Fish: 5 (all of them were feeding of of the rocks like last time)
Convict Tang: 34 and 54; average: 44 (these seem to be the most abundant type of fish.)
Yellow Goatfish: 9
Humuhumunukunukuapuaa(state fish): 7 8; Average 7.5
Raccoon Butterfly: 8 and 6 average: 7
Orange spine unicorn fish: 10 (all seen together in a shoal)
Moorish Idol: 4
Black spotted Sergeant fish: 7 and 9; average 8
Unicorn fish: 4 and 8; Average 6Needle fish: 8

Swim 1
Swim 2
Swim 3
Swim 4
Convict Tang
60
26
34
54
Orange Spine Unicorn Fish
7
10


Racoon Butterfly
6
1
8
6
Eel
1
1


Needle/Cornet Fish
1
1
8

Parrot Fish
1
3
4
5
Morish Idol
3
1
4

Hawaiian White Spotted Tobi
5
5
3

Humuhumunukunukuapuaa
7
7
8

Unicorn Fish
3
4
8

Ulua
2



Black Spotted Sergeant
6
8
7
9
Hawaiian Dascyllus
4



Yellow Goatfish
7
9


Above is the graph of all the fish counts for each speices we saw and counted. Not all the fish were counted equal numbers of times, becasue they were not always spotted more than once (such as the Ulua). Here is a general data table of the amount of fish per one swim. (swim 1 is not nescassarily the first day, same with swim 2 is not nescassarily 2nd day, etc,etc. The swim refers to the fish time the fish was counted. See above in the previous journal entries for details.
The convict tang is the most abundant of the fish. There far out number the other species of fish. This could be because they outcompete the other species. They could be more fit to their niche and are better at avoiding predation, breeding, feeding, or have an overall better immune system to help them avoid diseases. These fish could have reproduced much more because there is a great amount of food for them and they are good at eating it before other fish do. Another reason there could be such an abundance of the convict tangs is that the other fish around that area do not primarily live there, but are just passing through or stopping for a bite to eat. It could be that these fish are not any better suited than the other fish, but they just live in that certain area and therefore have populated it more than the other fish that are passing through and might live even farther out in the water beyond the rock wall. Both could be likely answers. I think that they must be good competition to the other fish which lead them to populate and live in that area. I believe that both are true, but that the first lead to the second.

This time instead of just counting a certain number of species i also counted the total number of fish seen on one swim and I did this five times. (five in the morning and five in the afternoon). I would swim out to the wall and try to keep a consistent pace, which would take about 6-7 minutes to go there and back. I would look for all fish within eye sight and count them. Though I may have counted the same ones twice or missed some the fish I did the exact same procedure for all of the trials and both of these variables would have effected all of the trials.I did not count just a certain species and ignore the rest, I counted every fish I saw.

Total fish count:Morning:139, 114, 96, 106, 123; Average = 116
Afternoon:78, 89, 88, 104, 82; Average = 88

Though this test was conducted just once and on the same day, there is clearly a trend. There are, on average, more fish out in the mornign than there are in the afternoon. I tried conducting the experiment because whenever my dad wanted to go snorkeling he would always make up wake up at 6 o clock in the morning to go because he said that there were more fish out. I was never sure why the fish were out, but i can infer that they are most likely out to feed or avoid being eaten. These seem like the most likely reason for there to be more fish on the shallow rocks feeding off the coral (which a majority of them were).
Temperature of..:shoreline water: 80F
15 feet out: 78.8F
Near rocks: 76.5F
Water pH: 7.9
Air temperature:82F

The temperatures were all slightly colder, but that is because it was a colder day. They still followed the same trend; the water got colder farther out. I think that the pH dropped because there was not enough sunlight and therefore photosynthesis did not occur as much as it had before. Without sunlight the plants/algae/coral could not photosynthesize and therefore not take in as much CO2 which could have raised the pH of the water. Another reason for this would be that the rain water had a lower pH than the ocean water because it is freshwater, which typically has a lower pH. The large amounts of rain could have lowered the pH as well.

Carbon cycle:

The carbon cycle in Hanauma bay is much like the snails and elodea lab. The animals in the bay: fish, crabs, eels, sea urchins, shrimp, etc are the consumers of this ecosystem. They give off carbon dioxide when they respire and they take in oxygen. The plants such as algae use photosynthesis and produce oxygen and take in carbon dioxide. The water also absorbs oxygen and carbon dioxide form the atmosphere. The atmosphere contains oxygen and carbon from the land plant and animals who respire and photosynthesize like the marine life does. The atmosphere also contains carbon from human activities such as the burning of fossil fuels. Since there has been so much CO2 in the atmosphere the ocean is absorbing more of it too making certain places 'dead zones' devoid of life becasue of the high CO2 level and low pH. Dead decaying matter also adds CO2 to Hanauma Bay (in and out of water). The plants on the beach around Haunama bay and surrounding it are some main CO2 intakers and oxygen suppliers to this area.